[PATCH][next] reset: npcm: check for NULL return from syscon_regmap_lookup_by_compat

From: Colin King
Date: Fri Nov 08 2019 - 10:55:30 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Function syscon_regmap_lookup_by_compat can return a NULL pointer, so
the IS_ERR check on the return is incorrect. Fix this by checking for
IS_ERR_OR_NULL and return -ENODEV if true. This avoids a null pointer
dereference on gcr_regmap later on.

Addresses-Coverity: ("Dereference null return (stat)")
Fixes: b3f1d036f26d ("reset: npcm: add NPCM reset controller driver")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/reset/reset-npcm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/reset/reset-npcm.c b/drivers/reset/reset-npcm.c
index 2ea4d3136e15..9febf8bed2f6 100644
--- a/drivers/reset/reset-npcm.c
+++ b/drivers/reset/reset-npcm.c
@@ -161,9 +161,9 @@ static int npcm_usb_reset(struct platform_device *pdev, struct npcm_rc_data *rc)
of_match_device(dev->driver->of_match_table, dev)->data;

gcr_regmap = syscon_regmap_lookup_by_compatible(gcr_dt);
- if (IS_ERR(gcr_regmap)) {
+ if (IS_ERR_OR_NULL(gcr_regmap)) {
dev_err(&pdev->dev, "Failed to find %s\n", gcr_dt);
- return PTR_ERR(gcr_regmap);
+ return -ENODEV;
}

/* checking which USB device is enabled */
--
2.20.1